This application claims benefit of priority under 35 U.S.C. Section 119 of Japanese patent application No. 10-070379 filed in the Japanese Patent Office on Mar. 19, 1998 and the entire contents of which are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to an electrophotographic image forming apparatus, such as, a color photocopier or a color printer, that is used in a network system as a shared-printer for a plurality of print-data-outputting apparatuses, such as client-computers or image scanners, and more particularly to an image forming apparatus having an anti-counterfeiting function for articles whose reproduction is forbidden by law, such as, paper currency bills, securities, postage stamps, and so forth.
2. Discussion of the Background
Current image forming apparatuses, such as, a color photocopier or a color printer, are capable of producing a counterfeit article whose reproduction is forbidden by law, such as, paper currency bills, securities; and so forth. Therefore, it is desired to provide an image forming apparatus with functionality of recognizing an article whose reproduction is forbidden by law, and inhibiting an ordinary reproduction thereof In particular, when an image forming apparatus is used in a network system as a shared-printer, it is desired that the apparatus determine if print-data, which has been sent via a network from one of the client-computers or image scanners as a print-data-outputting apparatus includes data for an article whose reproduction is forbidden by law, and take action to prevent the ordinary reproduction of the print-data if the print-data includes data of such an article.
Japanese Laid-open Patent Publication No. 23218/1995 describes a color printer which includes a data receiving device, a memory storing a plurality of data relating to specific articles whose reproduction is forbidden by law, such as paper currency bills, and means to apply a predetermined image-processing function to received data when the received data coincides with one of data stored in the memory, so as to cause the reproduction of the received data to be black or altered.
Japanese Laid-open Patent Publications No. 47717/1995, 123249/1995, 288681/1995, and 2010/1966, describe anti-counterfeiting devices, in which received print-data is judged according to whether reproduction of the print-data is forbidden by law, and if so the print-data is altered, and the altered print-data is outputted.
Generally, a printer or a digital photocopier can be connected to a network system, besides being used as a stand-alone apparatus, for use as a shared-image-outputting-device of the network system. A digital photocopier may also function as a network shared-image-inputting-device as well. A shared-image-outputting-device and a shared-image-inputting-device are often referred to as a shared-printer and a shared-scanner, respectively. A network system generally includes an arbitrary number of client-computers, server-computers, shared-printers, and shared-scanners, and is configured so that, every client-computer or shared-scanner may be used as a print-data-outputting apparatus by outputting print-data to one of the network""s shared-printers in order to output a hardcopy of the print-data. Therefore, if and when the printing device outputs a hardcopy of a specific article, such as paper currency bills or securities, whose reproduction is legally forbidden, the fidelity of the reproduction is lost by alteration of the article""s print-data so that the hardcopy can be easily recognized as an illegal reproduction. Also, the identity of the client-computer which outputted print-data for an article whose reproduction is legally forbidden or the network system user who intentionally or unintentionally attempted such an illegal reproduction, cannot be readily recognized from such a hardcopy.
The present invention has been made in view of the above-discussed problems and an object of the invention is to provide an image forming apparatus for use within a network system, wherein upon receiving print-data legally forbidden for reproduction from a print-data-outputting apparatus of the network system, the image forming apparatus prints in an altered paper reproduction of an image which indicates the identification code of the specific print-data-outputting apparatus which sent the print-data, such that the print-data-outputting apparatus which attempted illegal reproduction is easily recognized from the hardcopy.
Another object of the present invention is to provide an image forming apparatus able to prevent the reproduction of any print-data received from a print-data-outputting apparatus, which has output print-data whose reproduction is illegal, regardless of the legitimacy of reproduction of the later received print-data.
A preferred embodiment of the present invention comprises an image forming apparatus for use in a network system including a plurality of print-data-outputting apparatuses, each of which is able to send via the network print-data including information regarding the identity of the print-data-outputting apparatus to an image forming apparatus for outputting a hardcopy reproduction of the print-data. The image forming apparatus includes a print-data-receiving device configured to receive print-data from each of the plurality of network print-data-outputting apparatuses, a judging device configured to determine whether or not reproduction of the received print-data is legally forbidden by recognizing characteristics of the received print-data, an image-processing device configured to alter any forbidden print-data received so as to cause the fidelity of the reproduction of the forbidden print-data received to be lost or deteriorated, and to add to the altered print-data identification information regarding the identity of the specific print-data-outputting apparatus sending forbidden print-data, a control device configured to activate the image-processing device when the judging device determines that legally forbidden print-data has been received in a request for reproduction, so as to alter the forbidden print-data received and to add to the altered print-data identification information regarding the identity of the print-data-outputting apparatus sending the forbidden print-data, and a printing device that prints an altered image reproduction of the print-data and added identification information on a sheet of paper output as a hardcopy.